In so-called MicroElectroMechanical Systems MEMS, a movable part can be realized on a chip. Membranes used for static and/or dynamic pressure measurements, for example, are known here. In this case, the electrical measurement is usually effected capacitively or piezoresistively. So-called structures anchored on one side, also known as “micro-springboards”, are also known, which are often used as acceleration sensors. Other conventional movable or oscillating systems are disclosed in US 2010/0072626.
In a conventional “wafer-level packaged” integrated circuit, an MEMS is integrated in a first semiconductor layer. A thin-film layer is applied on the first semiconductor layer and arranged in such a way that it seals the cutout of the first semiconductor layer. At least one further layer is applied on the sealing thin-film layer and a so-called “under bump metallization” is arranged on the sealing thin film for the purpose of contact-connection. Such microstructures are very small since they are usually realized by etching processes on small semiconductor chips. Resulting from this, the correspondingly moved masses or volumes are very small. This fact may restrict the deflection amplitudes and frequency ranges obtainable therewith such as natural oscillation properties and hence the spreading of such technologies in corresponding applications.
One possibility for solving this issue consists in using small membrane and tongue structures, typically having thicknesses in the sub-μm range and up to 10 μm. The resulting lateral extents are thus in the range of <0.5 mm. The technologies used are usually etching and sacrificial technologies from microsystems engineering, also known as surface or bulk micromachining. Disadvantages here include, for example, the small mass and the small lateral extent of the movable parts of the corresponding structures.